Automatic displacer clearance adjustment

ABSTRACT

An apparatus and method producing a plait-like portion on a tubular packaging casing, which accommodates a filling material includes a plait-like portion at least approximately free of filling material, extending along a longitudinal plait-axis. The apparatus comprises a first displacer unit with a first pair of displacer elements reversibly movable between an opened and a closed position perpendicular to the longitudinal plait-axis. A displacer clearance is created between the first pair of displacer elements, which surrounds the longitudinal plait-axis, in which the tubular packaging casing is being gathered, when the first pair of displacer elements is in the closed position. The apparatus comprises a second displacer unit with a second pair of displacer elements also being reversibly movable between an opened and a closed position perpendicular to the longitudinal plait-axis. A displacer clearance is created between the second pair of displacer elements, similar to first pair of displacer elements.

CROSS REFERENCE TO RELATED APPLICATIONS

This patent application claims priority to and the benefit of Europeanpatent application EP 09 015 524.3-1260, filed Dec. 15, 2009, which ishereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to an apparatus and a method for producinga plait-like portion on a tubular packaging casing according to thepreamble of independent claims 1 and 10.

In particular, the invention concerns an apparatus for producing aplait-like portion on a tubular packaging casing which accommodates afilling material in particular sausage meat, wherein the plait-likeportion is at least approximately free of filling material and comprisesalong a longitudinal plait-axis. The apparatus comprises a firstdisplacer unit with a first pair of displacer elements being reversiblymovable perpendicular to the longitudinal plait-axis between an openedand a closed position. A displacer clearance is being created betweenthe first pair of displacer elements, which surrounds the longitudinalplait-axis and in which the tubular packaging casing is being gathered,when the first pair of displacer elements is in the closed position.Beyond that, the apparatus comprises a second displacer unit with asecond pair of displacer elements also being reversibly movableperpendicular to the longitudinal plait-axis between an opened and aclosed position. Again, a displacer clearance is being created betweenthe second pair of displacer elements, which surrounds the longitudinalplait-axis and in which the tubular packaging casing is being gathered,when the second pair of displacer elements is in the closed position.The second displacer unit is reversibly movable parallel to thelongitudinal plait-axis between a narrow position in which the firstdisplacer unit is adjacent to the second displacer unit, and a spreadposition in which the second displacer unit is moved away from the firstdisplacer unit. Furthermore, the apparatus comprises a first drive unitfor the movement of the first and second pair of displacer elementsbetween the opened and closed position. The first drive unit comprisesan adjustment device rotatable around a pivot axis essentially parallelto the longitudinal plait-axis.

Moreover, the invention concerns method for producing a plait-likeportion on a tubular packaging casing which accommodates a fillingmaterial in particular sausage meat, wherein the plait-like portion isat least approximately free of filling material and extends along alongitudinal plait-axis. The method includes the steps of conveying of afilling material into a tubular packaging casing and constricting thefilled tubular packaging casing by moving a first pair of displacerelements of a first displacer unit and a second pair of displacerelements of a second displacer unit from an opened into a closedposition by means of a first drive unit. Furthermore, a displacerclearance is created between the first and second pair of displacerelements surrounding the longitudinal plait-axis, in which the tubularpackaging casing is being gathered when the first and second pair ofdisplacer elements are in the closed position. Thereafter, a plait-likeportion is produced by moving the second displacer unit parallel to thelongitudinal plait-axis away from a narrow position in which the seconddisplacer unit is adjacent to the first displacer unit, into a spreadposition in which the second displacer unit is away from the firstdisplacer unit.

It is the usual practice in sausage production, to use for exampleautomatic clipping machines for filling e.g. sausage meat via a fillingtube into a flexible packaging material, like a tubular casing which isclosed by a closure means, referred to as closing clip, at the firstend. After the filling operation is concluded, a gathered plait-likeportion, which is free of filling material, is formed by two displacerunits. Two more clips are then applied to that plait-like portion, afirst closing clip in order to close the second end of the filledpackaging material and a second closing clip in order to close the firstend of the subsequent sausage product. Thereafter, said plait-likeportion is severed between said two clips creating one complete sausageproduct and packaging material closed at its first end to be filled, inorder to form the next sausage product. Such a practice for producingsausages is disclosed, for example, by EP-patent application 1 967 073A1 or DE-Utility model 20 2006 012 324 U1.

After the filling process, the sausage products can be sometimessubjected to further processing, for example in a smoking chamber orthey are just being packed in a box for shipping.

The different sausage products are typically characterized by a numberof parameters, such as caliber (i.e. the actual diameter of the sausageproduct), overall length, specific type of the filling material as wellas packaging casing material etc. Also, it is possible to vary thedensity of the filling material, in order to produce loosely filled ortightly filled sausage products, by injecting more or less fillingmaterial into the casing. However, in case of a tightly filled sausageproduct, these sausage products are rather prone to damages on thecasing, due to the high pressure inside the sausage product and theoften thin and sensitive casing material. Impacts, falls and other kindsof careless handling can result inevitable in notable damages to thesausage products, which lead to outcast and unnecessary costs. Aparticular problem in this context constitutes within the actualprocedure of constricting the casing by means of the two displacer unitsand forming the plait-like portion out of the tubular packaging casing.Depending on the above mentioned parameters, in particular, sensitivecasing material or “normal” casing material which is filled with sausagemeat at high pressure may be damaged during the constricting processwhen executed at a “normal” speed. Moreover, the casing material may bealso damaged during forming the plait-like portion.

SUMMARY OF THE INVENTION

The object of the present invention is to solve the above describedproblem. In particular, it is the object of the present invention toprovide an apparatus according to independent claim 1 and a methodaccording to independent claim 10 for producing a plait-like portion ona tubular packaging casing, with which the risk of damaging the casingmaterial while constricting said material and forming a plait-likeportion will be reduced and the productivity in the production ofsausage like products is raised.

What is proposed, in particular, is an apparatus for producing aplait-like portion on a tubular packaging casing which accommodates afilling material in particular sausage meat, wherein the plait-likeportion is at least approximately free of filling material and comprisesa longitudinal plait-axis. The apparatus comprises a first displacerunit with a first pair of displacer elements being reversibly movableperpendicular to the longitudinal plait-axis between an opened and aclosed position. A displacer clearance is being created between thefirst pair of displacer elements, which surrounds the longitudinalplait-axis, in which the tubular packaging casing is being gathered,when the first pair of displacer elements is in the closed position.Beyond that, the apparatus comprises a second displacer unit with asecond pair of displacer elements also being reversibly movableperpendicular to the longitudinal plait-axis between an opened and aclosed position. Again, a displacer clearance is being created betweenthe second pair of displacer elements, which surrounds the longitudinalplait-axis, in which the tubular packaging casing is being gathered,when the second pair of displacer elements is in the closed position.The second pair of displacer elements is reversibly movable parallel tothe longitudinal plait-axis between a narrow position in which the firstdisplacer unit is adjacent to the second displacer unit, and a spreadposition in which the second displacer unit is moved away from the firstdisplacer unit. Furthermore, the apparatus comprises a first drive unitfor the movement of the first and second pair of displacer elementsbetween the opened and closed position. The first drive unit comprisesan adjustment device rotatable around a pivot axis essentially parallelto the longitudinal plait-axis.

According to the present invention, it is proposed that the pivot axisof the adjustment device is adjustable for changing the size of thedisplacer clearance created by the first and second pair of displacerelements. Adapting the size of the displacer clearance depending on thecross-section area of the plait-like portion optimizes the voiding ofthe filling material from the plait-like portion.

Also, adapting the size of the displacer clearance depending on e.g. thesensitivity of casing material or the caliber of the sausage product tobe produced, reduces the risk of damaging while gathering the casingmaterial and forming the plait-like portion.

It is advantageous that the adjustment device comprises a drive elementand a two-armed lever which are coupled to each other by a torquetransmission element in order to transmit the motion of the drivemechanism via a drive arm to the displacer units. The transmission ofthe motion from a drive mechanism to the displacer units canalternatively be done by a chain-drive, gear-drive, belt-drive or anyother possible means of transmission. The torque transmission elementcan be in form of a sliding block or likewise, to permit the driveelement and the two-armed lever to be shifted relative to each otherwhile allowing a continuously transmission of torque. In order tosupport this, it is also favorably that the torque transmission elementis attached to the two-armed lever and is extending into a radialaligned guide being part of the drive element, to allow the torquetransmission element to continuously transmit torque from the driveelement to the two-armed lever, even if the two-armed lever varies itsposition relative to the drive element.

To allow a variation of the position of the two-armed lever relative tothe drive element, it is possible that the adjustment device comprises abushing with an eccentric portion and a centric portion, in order toprovide two centers of rotation for the bushing. In this configuration,the two-armed lever is mounted onto the eccentric portion of thebushing, to allow the pivot axis of the two-armed lever to orbit aroundthe pivot axis of the drive element.

In order to facilitate the adjustment of the position of the bushing, ina preferred embodiment the adjustment device comprises a locking ringwith an eccentric adapter firmly connected onto the bushing.

A second drive unit can be provided to the apparatus for driving theadjustment device in a rotational motion. The second drive unit may beformed by a linear actuator, in order to convert rotary into linearmotion. However, it is also possible that the second drive is in form ofother kinds of motors. It is further advantageous, that the second driveunit comprises a lead screw with a lead screw nut, for the purpose ofproviding a purchase for leading off the motion of the drive unit.

With the aim of transmitting the linear motion of the drive unit ontothe adjustment device, the second drive unit advantageously comprises adrive rod connecting the lead screw nut with the locking ring. It isalso possible that the second drive unit is transmitting its actuationby other means, such as a gear-, belt-drive or other appropriate gears.Alternatively, the second drive unit can directly be mounted on theadjustment device.

With the purpose of control and adjust their actuation, it is furtheradvantageous that a control unit is linked to the first and second driveunits. In this case, the adjustment device may automatically be actuatedon the basis of data regarding the sausage products actually to beproduced.

It is the further object of the present invention to solve the abovedescribed problem by providing a method according to independent claim12 of the present. In particular, a method is provided for producing aplait-like portion on a tubular packaging casing which accommodates afilling material in particular sausage meat, wherein the plait-likeportion is at least approximately free of filling material and comprisesalong a longitudinal plait-axis. The method comprises the steps ofconveying of a filling material into a tubular packaging casing andconstricting the filled tubular packaging casing by moving a first pairof displacer elements of a first displacer unit and a second pair ofdisplacer elements of a second displacer unit from an opened into aclosed position by means of a first drive unit. Furthermore, a displacerclearance is created between the first and second pair of displacerelements surrounding the longitudinal plait-axis, in which the tubularpackaging casing is being gathered when the first and second pair ofdisplacer elements are in the closed position, and a plait-like portionis produced by moving the second displacer unit parallel to thelongitudinal plait-axis away from a narrow position in which the seconddisplacer unit is adjacent to the first displacer unit, into a spreadposition in which the second displacer unit is away from the firstdisplacer unit.

In accordance with the present invention, the method further comprisesthe step of changing the size of the displacer clearance created by thefirst and second pair of displacer elements by adjusting a pivot axis ofan adjustment device. By changing the size of the displacer clearance,the risk of damaging in particular sensitive casing material may bereduced. Moreover, an adaption may be made to the caliber of thesausage-like product to be produced e.g., in case of a larger caliber ofthe sausage product, to the additional casing material forming aplait-like portion of a respectively larger diameter.

The method further comprises the step of putting parameter of apre-selected product, which is to be produced, into a control unitcontrolling the adjustment device, from which in a preferred embodimenta signal corresponding to the parameter of the pre-selected product istransmitted from the control unit to the second drive unit driving theadjustment device. Thereafter, in accordance with the signal transmittedto the second drive unit corresponding to the parameter of thepre-selected product, a bushing of the adjustment device is positioned.

The above mentioned features of the inventive method allow anautomatically adjustment of the adjustment device on the basis of dataregarding pre-selected products. The adjustment of the size of thedisplacer clearance by means of the adjustment device may even be doneduring on-going production without having to stop the sausage-productmanufacturing process. Thereby, the sausage production may be improvedand increased. In particular, the voiding of the filling material fromthe plait-like portion will be optimized. Moreover, the risk of damagingthe casing material will be minimized while maintaining a constant orhigher production rate.

Other advantages and one embodiment of the present invention shall nowbe described with reference to the attached drawings. The term “top”,“bottom”, “left” and “right” used when describing the embodiment relateto the drawings orientated in such a way that the reference numerals andname of the figures can be read normally.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

In the drawings,

FIG. 1 shows a front view of the inventive apparatus;

FIG. 2 shows a side view of the inventive apparatus according to FIG. 1;

FIG. 3 shows a detailed view of the inventive adjustment device with adrive element in front of a two-armed lever coupled by a torquetransmission element;

FIG. 4 shows a detailed view on a two-armed lever together with upperand lower connecting rods; and

FIG. 5 shows a section view according to section C-C of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

The embodiment of the inventive apparatus described in the following isused within clipping machines for the production of sausage products.The inventive apparatus may also be used, of course, in production ofsausage-shaped products that are not foodstuffs, but for example,sealing compounds or adhesives.

FIG. 1 shows a schematic front view of the inventive apparatus accordingto a preferred embodiment in perspective direction perpendicular to alongitudinal plait-axis 77, together with first and second drive units10, 90, a first displacer unit 50 a having a first pair of displacerelements 60 a and a second displacer unit 50 b having a second pair ofdisplacer elements 60 b. The first and second displacer units 50 a, 50 bare actuated by the first drive unit 10 for a reversible movementperpendicular to the plait-axis 77 along vertical displacer guide rods.FIG. 1 shows only the first displacer guide rod 72 along which the firstpair of displacer elements 60 a is vertically slidable. The apparatusaccording to the present invention comprises an adjustment device 20 aswell as a second drive unit 90 actuating the adjustment device 20.

FIG. 2 shows a schematic side view of the inventive apparatus accordingto a preferred embodiment in perspective direction of the longitudinalplait-axis 77, together with first and second drive units 10, 90 andfirst and second displacer units 50 a, 50 b actuated by the first driveunit 10.

FIG. 2 shows a first displacer unit 50 a together with upper and lowerdisplacer elements 62 a, 62 b. The upper and lower displacer elements 62a, 62 b are connected by upper and lower displacer element supporters66, 68 onto upper and lower displacer guide sleeves 74 a, 74 b, whichare slidable along the displacer guide rod 72.

In FIG. 2, the upper and lower displacer elements 62 a, 62 b are in theclosed position. That means, the upper displacer element 62 a is in itslowest position, whereas the lower displacer element 62 b is in itsupper most position. In the closed position, the upper and lowerdisplacer elements 62 a, 62 b form a displacer clearance 78.

The upper displacer guide sleeve 74 a can be slided from its currentposition as shown in FIG. 2, further upwards, in order to move the upperdisplacer element 62 a into the opened position, whereas the lowerdisplacer guide sleeve 74 b can be slided from its current positionfurther downwards, in order to move the upper displacer elements 62 binto the opened position. The first displacer unit 50 a is in the openedposition, when the upper displacer element 62 a of the first displacerunit 50 a is in a maximum linear displacement to the lower displacerelement 64 a.

FIG. 1 and FIG. 2 further show the first drive unit 10 comprises a drivearm 12 in form of a longitudinal lever 16 with a gear wheel section 15at its end pointing towards the adjustment device 20. The other end ofthe lever 16 (not shown) is mounted onto a drive (not shown) of thefirst drive unit 10 for pivotal driving the drive arm 12.

The adjustment device 20 comprises a drive element 30, a two-armed lever40, a bushing 25, a torque transmission element 24 and a locking ring80.

The drive element 30 is in form of a flat circular disc with a gearwheel section 31 located on its outer edge and two drive element guidearms in form of a left-hand and right-hand longitudinal bars 34 a, 34 bdefining a radial aligned notch 35 between them, as illustrated moreparticularly in FIG. 3.

As it can be inferred from FIG. 4, the two-armed lever 40 comprises aflat longitudinal panel 43 with a round centre hole 41, a two-armedlever attachment 46 formed by an eccentric belly, and two adapters 42 a,42 b in form of arms. A bolt 44 in form of a cylindrical shaftorientated parallel to the longitudinal plait axis 77 is firmly fittedwith one end to the two-armed lever attachment 46. The two adapters 42a, 42 b are symmetrical to a plane running through the centre of thetwo-armed lever 40 parallel to the plait-axis 77, and fitted with holesextending parallel the plait-axis 77 at each ends. The two adapters 42a, 42 b are connected by pins 48 a, 48 b to first ends of longitudinalconnecting rods 45 a, 45 b, which are positioned with their middlecentre line 47 perpendicular to the plait axis 77 (see also FIGS. 3 and5). The second ends of the longitudinal connecting rods 45 a, 45 b areconnected via upper and lower guide sleeve adapter pins 76 a, 76 b tothe displacer guide sleeves 74 a, 74 b. The displacer guide sleeves 74a, 74 b are slidably fitted around displacer guide rods 72, arrangedperpendicularly to the plait-axis 77 in a vertical orientation, in orderto slide up and down the displacer guide rods 72.

The torque transmission element 24 is formed by a sliding block with asquare cross-section fitted between the left-hand and right-handlongitudinal bars 34 a, 34 b within the notch 35 of the drive element30. The sliding block 24 comprises a centre hole through which thetwo-armed lever bolt 44 is fitted (see also FIG. 3 and FIG. 5).

Drive element 30 and two-armed lever 40 are positioned on a drive unitshaft 22. Drive unit shaft 22 thereby extends through centre holes 37,41 of drive element 30 and two-armed lever 40. Drive unit shaft 22 isfirmly coupled with its right-hand side end, as shown in FIG. 5, todisplacer guide rod 72, in a horizontal orientation, parallel to plaitaxis 77.

Drive arm 12 of the first drive unit 10 is connected to the adjustmentdevice 20 by its gear wheel section 15 engaging the gear wheel section31 of the drive element 30, in order to transmit the torque created bythe first drive unit 10 to the drive element 30.

The torque of drive element 30, received by the drive arm 12, istransmitted onto the two-armed lever 40 by the torque transmissionelement 24.

As illustrated in FIG. 5, the drive element 30 is arranged in front ofthe two-armed lever 40 that means to the left-hand side of the two-armedlever 40. As it can be further inferred from FIG. 5, a bushing 25 ispositioned onto the drive unit shaft 22 having an inner diametercorresponding to the outer diameter of drive unit shaft 22. The bushing25 extends through the centre hole 37 of drive element 30 and the centrehole 41 of the two-armed lever 40. Bushing 25 comprises a centricportion 27 and an eccentric portion 29, which are both formed ascylinders and positioned in their longitudinal direction offset to eachother. The drive element 30 is fitted onto the centric portion 27 of thebushing 25 and the two-armed lever 40 is positioned onto the eccentricportion 29 of the bushing 25. The centric portion 27 has a pivot axis 36and the eccentric portion has a pivot axis 47. Due to the off-centrealignment of the centric portion 27 and the eccentric portion 29, thepivot axis 36 is not identical to the pivot axis 47. A bearing ispositioned between the centric portion 27 and the drive element 30 toreduce friction between bushing 25 and drive element 30 during pivotalmovement of drive element 30 about the centric portion 27 of bushing 25.The centre line of the centric portion 27 as well as the centre line ofthe eccentric portion 29 are both parallel to the plait axis 77.

The locking ring 80 is firmly attached around the front end of centricportion 27 of the bushing subjecting from drive element 30. A lockingring cover disc 81 is attached to the left-hand side end of the driveunit shaft 22 by means of a locking ring screw 86, covering the frontend of the centric portion 27 of the bushing 25 (see FIGS. 1 and 5).

FIG. 2 shows the second drive unit 90 comprises a motor 92, alongitudinal lead screw 100 and a drive rod 108.

The motor 92, according to the present embodiment, is in form of anelectric motor, which is attached to a frame element (not shown) andwhich comprises a drive shaft (also not shown). A gear drive 93 isconnected to the upper end of the drive shaft of the motor 92.

The lead screw 100 comprises a lead screw gear 95 at its upper endpointing away from the adjustment device 20. The centre line 101 of thelead screw 100 extends perpendicular to the plait axis 77 and parallelto the drive shaft of the motor 92. A lead screw nut 102 having with around lead screw nut adapter 104 is fitted onto the lead screw 100. Aroller chain 94 is connecting the gear drive 93 with the lead screw gear95.

Left-hand and right-hand lead screw guide rods 106 a, 106 b are arrangedparallel to lead screw 100, one on the left-hand side and one on theright-hand side of the lead screw 100, as it can be inferred from FIG.2. Lead screw nut 102, which is driven along the lead screw 100,comprises extensions on its left- and right-hand sides forming sleeves103 for engaging left-hand and right-hand lead screw guide rods 106 a,106 b.

Drive rod 108 comprises a longitudinal drive rod shaft 107 with circularupper and lower drive rod adapters 105 a, 105 b. Drive rod 108 isorientated with its centre line 109 perpendicular to the plait axis 77.The upper drive rod adapter 105 a is pivotal connected to the lead screwnut adapter 104 and the lower drive rod adapter 105 b is pivotalconnected to the locking ring adapter 82 of locking ring 80.

The present inventive apparatus also comprises a control unit 110(schematically shown in FIG. 2). The control unit 110 is connected tothe first drive unit 10 and second drive unit 90, in order to feedinformation into them and to control the actuation of the drive units10, 90. It is also possible that one control unit is connected to thefirst drive unit 10 and a separate control unit is connected to thesecond drive unit 90, and that these two control units are being linkedto each other to cross function.

When the drive arm 12 is being put into a pivotal motion by the firstdrive unit 10, the drive arm 12 is moved reversibly from side to side ina given frequency. The torque created by the drive arm 12 is beingtransmitted onto the drive element 30 by means of the gear drive 14, asthe gear wheel section 15 of the drive arm 12 is engaging the gear wheelsection 31 of the drive element 30. Due to the transmitted torque to thedrive element 30, the drive element 30 is pivotally rotating about agiven amount reversibly into clockwise and anti-clockwise directionabout pivot axis 36. The torque of drive element 30 is being transmittedby means of the torque transmission element 24 to the two-armed lever40, left-hand or right-hand longitudinal bars 34 a, 34 b onto the squarecross sectioned sliding block. The received torque is furthertransmitted via the two armed lever bolt 44 onto the two-armed lever 40for rotating the two-armed lever 40 about a given amount reversibly intoclockwise and anti-clockwise direction. By rotating the two-armed lever40 two-armed lever adapter 42 a is being pushed either upwards ordownwards perpendicular to the plait-axis 77. In the same way, but inopposite direction to the up and down movement of two-armed leveradapter 42 a, is two-armed lever adapter 42 b is being pushed either upor down perpendicular to the plait-axis 77. As the left-hand and theright-hand two-armed lever adapters 42 a, 42 b are being pushed eitherupwards and/or downwards perpendicular to the plait axis 77, the upperand lower displacer guide sleeves 74 a, 74 b are also being pushedeither upwards and/or downwards along the displacer guide rod 72 byupper and lower connecting rods 45 a, 45 b connecting two-armed leveradapter 42 a, 42 b to upper and lower displacer guide sleeves 74 a, 74b. By moving the upper and lower displacer guide sleeves 74 a, 74 b upand down along the displacer guide rod 72, the upper and lower displacerelements 62 a, 62 b, 64 a, 64 b are also being reversibly moved betweentheir opened and closed position, as they are respectively connected tothe upper and lower displacer guide sleeves 74 a, 74 b by means of theupper and lower displacer element supporters 66, 68.

By feeding the relevant information regarding the parameter of theto-be-produced sausage product into the control unit 110, which isconnected to the second drive unit 90, the drive shaft (also not shown)of the motor 92 is being turned about a pre-determined amount in respectto the parameter of the to-be-produced sausage product. The drive gear93 is being turned, as it is connected to the driveshaft of the motor92. The rotational motion of the drive gear 93 is being transmitted viaroller chain 94 onto lead screw gear 95. The rotational motion of thelead screw gear 95 is transmitted onto lead screw 100, causing the leadscrew nut 102 to travel either upwards (i.e. away from the adjustmentdevice 20) or downwards (i.e. towards the adjustment device 20) alongthe lead screw 100. Left-hand and right-hand lead screw guide rods 106a, 106 b on each side and parallel to the lead screw are preventing thelead screw nut 102 from rotating around the lead screw 100, as the leadscrew nut sleeves 103 are slidably engaging the left-hand and right-handlead screw guide rods 106 a, 106 b. Since the lead screw nut adapter 104is connected to the upper drive rod adapter 105 a, the drive rod 108 ispushed in the same direction as the lead screw nut 102. The lower driverod adapter 105 b is turning the locking ring adapter 82, depending onthe upwards or downwards direction of the drive rod 108, eitherclockwise or anti-clockwise direction. The locking ring 80 istransmitting its received torque from the drive rod 108 via centricportion 27 onto the eccentric portion 29 of the bushing 25, causingpivot axis 47 of two-armed lever 40 to be moved along a circle aboutpivot axis 36 of drive element 30. The amount of the movement of thepivot axis 47 corresponds to the amount of the movement of locking ring80.

As the pivot axis 47 of two-armed lever 40 is being moved about apredetermined amount, the position of two-armed lever 40 has beenchanged relative to drive unit shaft 22 and to drive element 30,respectively. Thus, the upper and lower displacer elements 62 a, 62 b,64 a, 64 b are pushed respectively upwards and downwards in thedirection perpendicular to the plait axis 77, since they are connectedvia the upper and lower displacer element supporters 66, 68 and theupper and lower connecting rods 45 a, 45 b to the left-hand andright-hand two-armed lever adapters 42 a, 42 b.

Since, the drive element 30 rests slidable on the centric portion 27 ofthe bushing 29, the pivot axis 36 of drive element 30 is not being movedand stays stationary relative to drive unit shaft 22, as the lockingring 80 is applying a torque onto the eccentric portion 29 of thebushing 25, in order to move the pivot axis 47 of two-armed lever 40.

Also, as the torque transmission element 24 is in form of a square crosssectioned sliding block and being positioned within the notch 35 betweenthe two drive element guide arms 34 a, 34 b of the drive element guidenotch 35, the torque transmission element 24 is able to compensate therelative movement of the drive element 30 to the two-armed lever 40 andallows a reliable transmission of torque between drive element 30 andtwo-armed lever 40.

By moving the pivot axis 47 of the two-armed lever 40 relative to thepivot axis 36 of drive element 30, caused by adjusting bushing 25,two-armed lever 40 is also pivoted in its position relative to driveelement 30. During this adjustment, the closed position as well as theopened position of the upper and lower displacer elements 62 a, 62 b, 64a, 64 b are changed accordingly. The amount of which the two-armed lever40 is being moved is directly proportional to the amount of which theopened and closed position of the upper and lower displacer elements 62a, 62 b, 64 a, 64 b are being changed. In the case of changing theclosed position of the upper and lower displacer elements 62 a, 62 b, 64a, 64 b about a pre-determined amount, the displacer clearance 77 isbeing changed about an amount relative and in proportion to that amountof the change of the closed position of the upper and lower displacerelements 62 a, 62 b, 64 a, 64 b.

In other words, by adjusting the position of the bushing 25, inparticular the eccentric portion 29 of bushing 25, an adjustment of theopened and closed position of the displacer elements 62 a, 62 b, 64 a,64 b can be done as well as an adjustment of the diameter of thedisplacer clearance 77.

Thereby, it is possible to easily adapt the displacer clearance 77according to the respective parameters of the to-be produced sausageproducts. The adjustment of the size of the displacer clearance 77 mayeven be done during the on-going production without having to stop thesausage-product manufacturing process. The displacer clearance 77 can beincreased, if, for example, a sausage product with a larger diameter, athicker tubular packaging casing or a more rigid and dense fillingmaterial is to be produced, in order to create an appropriate plait-likeportion on a tubular packaging casing in respect to the cross-sectionarea of the plait-like portion and without damaging the sausage product.It is thereby possible to start-up the production process of the sausageproducts according to the pre-selected production parameters and tochange the size of the displacer clearance 77 during the productionprocess, in order to adapt or fine-tune the size of the displacerclearance 77 to the actual or changing production requirements.

LIST OF REFERENCES

-   1 Apparatus-   10 First drive unit-   12 Drive arm-   13 Free end of drive arm-   14 Gear drive-   15 Gear wheel section-   16 Longitudinal lever-   20 Adjustment device-   22 Drive unit shaft-   24 Torque transmission block-   25 Bushing-   27 Centric portion of the bushing-   29 Eccentric portion of the bushing-   30 Drive element-   31 Gear wheel section-   32 Drive element guide-   33 Disc-   34 a Left-hand drive element guide arm-   34 b Right-hand drive element guide arm-   35 Notch-   26 Pivot axis of centric portion 30-   37 Centre hole-   40 Two-armed lever-   41 Centre hole-   42 a Left-hand two-armed lever adapter-   42 b Right-hand two-armed lever adapter-   43 Panel-   44 Two-armed lever bolt-   45 a Upper connecting rod-   45 b Lower connecting rod-   46 Two-armed lever attachment-   47 Pivot axis of eccentric portion 40-   48 a Left-hand connecting pin-   48 b Right-hand connecting pin-   50 a First Displacer unit-   50 b Second Displacer unit-   60 a First pair of displacer elements-   60 b Second pair of displacer elements-   62 a Upper displacer element of first displacer unit-   62 b Lower displacer element of first displacer unit-   64 a Upper displacer element of second displacer unit-   64 b Lower displacer element of second displacer unit-   64 Lower displacer element-   66 Upper displacer element supporter-   68 Lower displacer element supporter-   70 Displacer guide-   72 Displacer guide rod-   74 a Upper displacer guide sleeve-   74 b Lower displacer guide sleeve-   75 a Upper displacer guide sleeve adapter-   75 b Lower displacer guide sleeve adapter-   76 a Upper displacer guide sleeve adapter pin-   76 b Lower displacer guide sleeve adapter pin-   77 Longitudinal plait-axis-   78 Displacer clearance-   80 Locking ring-   81 Locking ring cover disc-   82 Locking ring adapter-   84 Locking ring washer-   86 Locking ring screw-   90 Second drive unit-   92 Motor-   93 Drive gear of motor-   94 Roller chain-   95 Lead screw gear-   100 Lead screw-   101 Centre line of lead screw-   102 Lead screw nut-   103 Lead screw nut sleeve-   104 Lead screw nut adapter-   105 a Upper drive rod adapter-   105 b Lower drive rod adapter-   106 a Left-hand lead screw guide rod-   106 b Right-hand lead screw guide rod-   107 Drive rod shaft-   108 Drive rod-   109 Drive rod centre line-   110 Control unit

The invention claimed is:
 1. An apparatus for producing a plait-likeportion on a tubular packaging casing which accommodates a fillingmaterial, wherein the plait-like portion is at least approximately freeof filling material and comprises a longitudinal plait-axis, comprising:a first displacer unit with a first pair of displacer elements beingreversibly movable perpendicular to the longitudinal plait-axis betweenan opened and a closed position creating a displacer clearance betweenthe first pair of displacer elements surrounding the longitudinalplait-axis, in which the tubular packaging casing is being gathered,when the first pair of displacer elements is in the closed position, asecond displacer unit with a second pair of displacer elements beingreversibly movable perpendicular to the longitudinal plait-axis betweenan opened and a closed position creating a displacer clearance betweenthe second pair of displacer elements surrounding the longitudinalplait-axis, in which the tubular packaging casing is being gathered,when the second pair of displacer elements is in the closed position,the second displacer unit being reversibly movable parallel to thelongitudinal plait-axis between a narrow position in which the firstdisplacer unit is adjacent to the second displacer unit, and a spreadposition in which the second displacer unit is moved away from the firstdisplacer unit, and a first drive unit for the movement of the first andsecond pair of displacer elements between the opened and closed positionhaving an adjustment device rotatable around a pivot axis essentiallyparallel to the longitudinal plait-axis, wherein the pivot axis of theadjustment device is adjustable for changing the size of the displacerclearance created by the first and second pair of displacer elements,wherein the adjustment device comprises a drive element and a two-armedlever, which are coupled to each other by a torque transmission element,which is attached to the two-armed lever and extends into a radialaligned guide of the drive element.
 2. The apparatus according to claim1, wherein the adjustment device comprises a bushing with a centricportion and an eccentric portion.
 3. The apparatus according to claim 2,wherein the two-armed lever is mounted onto the eccentric portion of thebushing.
 4. The apparatus according to claim 2, wherein the adjustmentdevice comprises a locking ring with an eccentric adapter firmlyconnected onto the bushing.
 5. The apparatus according to claim 4,additionally comprising a second drive unit for driving the adjustmentdevice.
 6. The apparatus according to claim 5, wherein the second driveunit is a linear actuator.
 7. The apparatus according to claim 5,wherein the second drive unit comprises a lead screw with a lead screwnut.
 8. The apparatus according to claim 7, wherein the second driveunit comprises a drive rod connecting the lead screw nut with theadjustment device.
 9. The apparatus according to claim 5, wherein acontrol unit is linked to the first and second drive units.
 10. Theapparatus according to claim 5, wherein a control unit is linked to thefirst and second drive units.
 11. The apparatus according to claim 1,additionally comprising a second drive unit for driving the adjustmentdevice.
 12. The apparatus according to claim 11, wherein the seconddrive unit is a linear actuator.
 13. The apparatus according to claim12, wherein the second drive unit comprises a lead screw with a leadscrew nut.
 14. The apparatus according to claim 2, additionallycomprising a second drive unit for driving the adjustment device. 15.The apparatus according to claim 14, wherein the second drive unit is alinear actuator.
 16. The apparatus according to claim 15, wherein thesecond drive unit comprises a lead screw with a lead screw nut.
 17. Theapparatus according to claim 3, wherein the adjustment device comprisesa locking ring with an eccentric adapter firmly connected onto thebushing.
 18. The apparatus according to claim 17, additionallycomprising a second drive unit for driving the adjustment device. 19.The apparatus according to claim 18, wherein the second drive unit is alinear actuator; or the second drive unit comprises a lead screw with alead screw nut; or a control unit is linked to the first and seconddrive units.
 20. The apparatus according to claim 19, wherein the seconddrive unit comprises a lead screw with a lead screw nut; and a drive rodconnecting the lead screw nut with the adjustment device.